Scanned copies of historical census forms. The most recent census included is 1940.
The NHGIS provides free access to aggregate Census data and GIS-compatible boundary files for the United States from 1790-2010.
SimplyAnalytics is a web-based mapping, analytics and data visualization program providing data variables. Users have access to demographics, marketing data, consumer behavior (purchasing and product usage data), market segments, health, and business points for States, Congressional Districts, Counties, Cities/Places, ZIP Codes, Census Tracts and Block Groups. Users can also export data, maps, reports and shapefiles for use outside of SimplyAnalytics. Now includes Nielsen Scarborough Data Module.
The Integrated Public Use Microdata Series (IPUMS-USA) consists of more than fifty high-precision samples of the American population drawn from fifteen federal censuses and from the American Community Surveys of 2000-2012. These samples, which draw on every surviving census from 1850-2000, and the 2000-2012 ACS samples, collectively constitute our richest source of quantitative information on long-term changes in the American population. However, because different investigators created these samples at different times, they employed a wide variety of record layouts, coding schemes, and documentation. This has complicated efforts to use them to study change over time. The IPUMS assigns uniform codes across all the samples and brings relevant documentation into a coherent form to facilitate analysis of social and economic change.
ICPSR is a social science repository that includes curated data sets pertaining to many disciplines within the social sciences. ICPSR contains original codebooks and descriptions of methodology, offers multiple file format downloads, and links data to relevant scholarly research. Users can search at the variable level and trace datasets to their use in academic publications. The archive also includes data-driven learning guides for those teaching with data.